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Today, 09 February 2010

› Strike three, Mr President

› Cooked head discovered

› Zuma apology 'unwelcome'

› 'Illegal' traps blasted

› Madiba to grace Parliament

Yesterday, 08 February 2010

› No credit to FW - Zuma

› Zapiro revives showerhead

› 'Our president has failed'

› Praise for Amla

› 'Zuma should be forgiven'

This article on running injuries will cover muscle injuries. These fall into four categories according to Tim Noakes, in "The Lore of Running".

• Delayed muscle soreness
• Acute (sudden) muscle tears
• Chronic (insidious) muscle tears
• Muscle cramps

Delayed muscle soreness

This describes a feeling of muscle discomfort which comes on 24 to 48 hours after particularly extreme, or unaccustomed exercise.

It is not caused by lactic acid build up! The lactate concentration in these muscles is not raised. See Training and muscle metabolism for more on the lactate story.

It is likely that the pain is caused by damage to muscle cells, particularly in the connective tissue, and proteins concerned with muscle contraction.

There seem to be at least three types of muscle damage which occur with exercise. The first occurs 24 to 48 hours after unaccustomed exercise in trained people. This appears to be associated with leakage of muscle enzymes into the blood.

The second type of muscle soreness takes about four to six days to occur, and is found after unnacustomed exercise in untrained people. This is associated with much higher rates of enzyme leakage into the blood, and inflammation, and degeneration of muscle cells. This degeneration peaks ten to 12 days after exercise. The glycogen content of damaged muscles is also reduced, and by 20 days after exercise, replacement of damaged muscle cells is well advanced.

The third type of delayed muscle soreness seems to be associated with an increase in the concentration of inorganic phosphate within the muscles. Phosphate appears to accumulate at the point of damage.

Delayed muscles soreness indicates that the muscle has been overstressed, and is strong indicator of overtraining.

Prevention is the key to treatment. This involves distance training, training downhill, and weight training to increase the strength of the quadriceps muscle. Research has shown that a single bout of downhill training will protect muscles from damage during similar exercise for up to six weeks.

Acute muscle tears

This is the classic muscle injury of sprinters, squash players, and rugby players. There is sudden severe pain in the affected muscle, and running is impossible. The muscle is in spasm, extremely tender, and swells over the next few hours. There may be signs of bruising on the overlying skin.

These injuries are thought to result from a combination of muscle strength imbalance between opposing muscle groups, inflexibility of the affected muscles, and poor warm-up technique.

The immediate treatment is to apply ice to the tender area, to rest, and to elevate the limb. A firm compression bandage should be applied to the site of the tear as soon as the ice treatment is finished.

You then need to see someone experienced in the management of these injuries for further treatment and rehabilitation.

Chronic muscle tears

These are also called muscle knots, and are probably the commonest injuries seen in elite distance runners, and the third most common injury among all groups of runners.

The symptoms are of gradual pain, which initially comes on after exercise. At first it is possible to run through it. However, the pain becomes progressively worse, until it interferes with training. Eventually, speedwork in particular, becomes impossible.

The pain is almost always found only in a large muscle group, such as the buttocks, groin, hamstring, or calf muscles. It is deep seated, and very severe, but passes off rapidly with rest. The damaged muscle may also have gone into spasm.

Diagnosis is made by pressing firmly, with two fingers, into the affected muscle area. If a very tender, hard "knot" if located, then the injury is definitely a chronic muscle tear. It will not show up on x-ray!

It is not known how these injuries happen, but they seem to occur in muscles which are subjected to very high loading.

Treatment is by cross-friction, an excrutiatingly painful manoeuvre carried out by physiotherapists! According to Tim Noakes, this is the only thing which works. Most chronic tears will respond rapidly to five or ten sessions, lasting five to ten minutes per session. The pain should become gradually less while running, and longer distances can be covered as recovery takes place.

Muscle cramps and the stitch

Muscle cramps are painful, spasmodic, involuntary contractions of muscles. They are usually of little medical significance, although uncomfortable. They tend to occur at night, or during prolonged exercise.

Some people get cramps often, others seldom.

Cramps during prolonged exercise often come on in people who run further, or faster than they usually do in training.

There is no evidence that major disturbances in electrolytes are the cause of cramps.

A stitch is a cramp of the diaphragm muscle. It happens particularly when the person is running fast, and when breathing becomes uncomfortable. This causes panting, so the diaphragm muscle contracts, and never fully lengthens.

The stitch can be broken by exhaling fully, so stretching the muscle. It can also be prevented by taking deep breaths while running, rather than panting.